2006 TDI Weird Issue to Me...

[Rechtsverdreher]

The car was accidentally filled with gasoline. The corrective steps were to tow it home from where it stopped. (Car was loaned to someone who thought they were doing a good deed by filling it up after use). Fuel evacuated from tank and filter. New filter followed by new fuel pump, followed by used vacuum fuel pump on the end of the motor.
None of these issues have corrected the problem of the vehicle, while being driven, suddenly stopping and not starting again. It is usually towed home and then will start again after a while. This did not happen before the misfuel but maybe it is something that cropped up on its own. Don't know.
The car will start, run and drive until it doesn't, usually not near home but in the local area.
What can I check?

 

[turbodieseldyke]

New filter followed by new fuel pump, followed by used vacuum fuel pump on the end of the motor.

You replaced the tandem pump? Maybe the new/used one is no good.

 

[Rechtsverdreher]

Yes, replaced that tandem pump. Issue has remained, but would the tandem pump cause something like this? Not doubting, just asking. Thank you for the response!

 

[turbodieseldyke]

How is it being driven, when it dies? Is it during cruise, acceleration, or deceleration? When you say it won't restart, does it crank?

I'm only guessing that it's not getting fuel, but hopefully someone else has more experience that matches yours, and can point you in the right direction.

 

[Rechtsverdreher]

Good points. I think it dies when it is at a light...have to check with the driver. Yes, definitely cranks but won't start. Sounds like fuel issue but not sure what else it could be...probably related to the misfueling but...what?

 

[turbodieseldyke]

The only time my 06 died was on the freeway. I was trying to milk the last gallon, and when traffic started slowing down ahead, I kicked into neutral to coast, and it died. The tandem pump at 2000rpm was sucking enough fuel to keep running, but at 900rpm it petered out. After refueling and 30 seconds of cranking, i was on my way.

So until it gets fixed, maybe the driver can keep their foot on the gas at a stoplight to keep the rpms up and keep the fuel flowing. Sounds like some stupid trick I had to do on a carbureted car decades ago.

 

[Rechtsverdreher]

I don't know what it could be but my friend states that when he plays with the fuel lines, he can get it started...wondering if those lines should be exchanged?

 

[dtrvler]

Didnt need to replace tandem pump or in tank pump. Ive always fixed gasoline problems by draining fuel tank, filling with 5 or 10 gallons of diesel, changing fuel filter, draining fuel filter housing, running the in tank pump until diesel was coming out at the line into the tandem pump, bleeding the tandem pump at test port, cranking/running car to clear the rest of the gas out of the head and injectors. Its weird that this issue was kicked off by the misfuel. I'd put the old pumps back on and see if it runs. New parts doesnt always mean servicable parts.i try to keep the number of variables down to a minimum while troubleshooting.

 

[BuckeyeMan71]

I would check it out with a VCDS cable. Also I had partial same issue minus the wrong fuel and mine was the crank positioning sensor.

 

[Rechtsverdreher]

Thank you. dtrvler, we did all those. We sucked out the gasoline out of the tank, cleaned that tank, then got fuel into the lines. Changed filter, so pretty much followed that path you cite. The ONLY thing not done was the bleeding at the tandem pump! Could there be an air bubble in there and that's why its stalling? My friend stated he jiggled and messed with the fuel line the first couple times and then the third time sprayed starting fluid into the intake...not sure about that one, but he got it started.
I'm not sure about the crank positioning sensor but it sounds like that as well...outside of the issue starting after the misfuel.
Sooo, how do you bleed the tandem pump...is that on here somewhere? Of to do a search!

 

[dtrvler]

Here is the test port. You can bleed air out here:

 

[dtrvler]

http://imgur.com/r3C9HqF

 

[dtrvler]

That said, i would think any air would have bled out by now. It is weird

 

[dtrvler]

Make sure fuel lines are connected correctly:

http://imgur.com/DfyXl75

 

[Rechtsverdreher]

Thank you, I'll try the test port. Does the car have to be running when undoing the test port? Or just the key on? Do I open it up or do I open and close it quickly? Sorry for all the questions...haven't done this one before.

 

[dtrvler]

To bleed at test port, cycle the ignition w/o starting. Its the same as cking the in tank pump operation at the line from the tank at the filter housing...just further down the line. Just cycle the key until no bubbles. Into a big rag. Should be a nice clear stream. Then put the plug in without letting air back in.

 

[Rechtsverdreher]

Thank you, that's great information. I don't take that plug out, just loosen it?

 

[dtrvler]

Take it out then put it back without letting air in as much as possible.

 

[Rechtsverdreher]

Got it! Thank you!!!

 

[Rx7145]

I had the same problem (stalling) ended up being the in tank fuel filter was plugged. BRM Jetta.